Blood circulation is the process by which blood moves through the body, delivering oxygen and nutrients to cells while removing waste products. This system is primarily driven by the heart, which pumps blood through a network of arteries, veins, and capillaries. The arteries carry oxygen-rich blood away from the heart, while the veins return oxygen-poor blood back to the heart. The circulatory system is divided into two main circuits: the pulmonary circulation and the systemic circulation. In pulmonary circulation, blood travels from the heart to the lungs to pick up oxygen. In systemic circulation, oxygenated blood is distributed to the rest of the body, ensuring that all organs and tissues receive the necessary resources for proper function.